Patent GB-587756-A (GB)
Title: Improvements in automatic continuous or intermittent weight integrators and weight totalisers and recorders
IPC: G01G23/18
Filed: 1945-01-15
Abstract: 587,756. Weighing-apparatus. BROWN, S. C. Jan. 15, 1945, No. 1225. [Class 143] [Also in Groups XIX and XXXIV] In apparatus for automatically integrating the weight of materials conveyed continuously or intermittently of the kind including at least two rotating members one driven by the other through variable frictional transmission means adjustable under the control of a weight responsive element to vary the speed of the driven member in direct proportion to the extent of movement imparted to the frictional transmission member, the said rotating members being coupled through differential gearing with movable indicating or recording means, movements of the weight responsive element are transmitted to the frictional transmission member through an articulated parallelogram extending from above to below the friction gear and adapted to make angular movements directly proportional in extent to the movements of the weight responsive element, and means carried by the lower member of the parallelogram so as to be moved thereby parallel to itself and extending upwards therefrom and into engagement with the frictional transmission member, whereby a substantially linear relationship is obtained between the movements of the weight responsive element and the displacement of the frictional transmission element. The roller 4 of a conveyer belt is mounted in a weighing system comprising a platform 6 attached to rods 7, one each side of the belt, and shackled to the arms 9 of a weigh beam 10, one arm being shackled to a bell-cranked lever 13 carrying a pendulum weight 15. Alternatively the resistant may be a spring or depend on fluid displacement. The pendulum movements may indicate on a scale the hourly feed rate. The integrating. mechanism comprises a shaft 18 driven from a roller 20 or the belt-driving mechanism, and rollers 22, 23, Fig. 3, cylindrical and conical respectively, the former driven from the shaft 18, and the latter friction-driven by a ball 26, the lines of contact of the ball with the rollers being parallel and horizontal. Roller 22 is geared with a 2:1 ratio with the planet cage 24 of a gear 25, while roller 23 is geared with the planet pinions 28 so that when both rotate at the same speed the shaft of the sun wheel 29 which drives the recorder 30 is stationary. An articulated parallelogram comprises the bellcrank arm 13, a link 37, and an arm 36 pivoted thereto and extending from a bell-crank member having one arm 34 mounted on knife-edges on the weight 15 and the other arm 35 extending upwards and carrying a hinged arm 38 with a yoke 39 having disc wheels 40 for rolling engagement with the ball 26. Rocking of the weigh beam 10 causes the arm 35 to move parallel to itself and displace the ball 26. Magnets may be located below the rollers and ball to give firm contact. To alter the scale of measurement, the gearing between the sun wheel 29 and the integrating indicator 30 may be varied. Thus a detachable spider 43 has pins 44 for pinions 45 the number and size of which can be selected. A lettered wheel 47 reveals when the system is out of balance by movement of a sighted letter, and correction-is effected by a balance weight 95 on the pendulum arm 13. Where the conveyer is continually loaded, zero balancing is effected by raising a roller 49 on the idle run of the belt by means of handle 53 and toggle linkage 51, 52, and raising a roller 54 beneath the upper run to lift it from roller 4. The weigh beam thus takes the load of an empty belt section. More rollers may be lifted when fast running belts are used. For intermittent integration as with a train of trucks, a clutch may be provided between the differential and weight recorder, and a one revolution detent wheel to throw in the clutch for each truck. The roller 22 is driven continuously and geared to a clutch element the other element forming a detent wheel which is engaged by the action of a cam and lever mechanism tripped by each truck as it moves into the weighing position, while a further cam ring controls the operation of a clutch between the differential and recorder. The knife-edge bearings are provided with means for locking against movement and for self-alignment. The knife-edge member 77, Fig. 6, has a hole 78 countersunk at 79 to receive the coned part 83 of a screw 80 on tightening the latter, whereby the member 77 is raised from the bearing block 84 and locked. The block 84 has the usual V-groove and carries a pin 86 the ends of which extend beyond the block and are rotatable in a U-stirrup 87 embracing the block from below. The part of the pin in the V-groove makes point contact only with the sides of a notch 90 in the knife-edge. The block 84 and stirrup are journalled by means of a pin 91 to be partially rotatable so as to align them with the knife-edge, when locking may be effected by nut 93. Where more than one bearing is used in co-axial alignment, the remaining bearings are constructed with the pin 91 shaped so as not to interrupt the V-groove or replaced by two pins inserted in the opposite sides of the block. To record the weight at a distance, a commutator geared to the recorder may make and break an electric circuit to operate a rotary electric impulse recorder. Similar means may stop, start or vary the speed of mechanism used in operations when a predetermined amount of material has been weighed.